DE1069322B - Process and device for the production of lean gas of uniform quality by smoldering and gasifying ash-rich fuels in a cross-flow furnace - Google Patents

Description

GERMAN

PATENT OFFICE

KL.24e 13/01

INTERNAT. KL. C 10 j

M35856IVc / 24e

REGISTRATION DAY: NOVEMBER 8, 1957

NOTICE
THE REGISTRATION
AND ISSUE OF THE
EDITORIAL: NOVEMBER 19, 1959

The invention relates to the production of combustible gases by smoldering and gasifying ash-rich Fuels, in particular wash mountains and bituminous rocks such as oil shale. For this procedure ovens are used through which the goods can pass from one end to the other own weight or by special means of conveyance is moved through it, while the Schwelung and Gasification causing gases are passed through the material layer transversely to the conveying direction. Such cross-flow ovens are designed in the form of traveling grids, inclined chambers with advancing grids or vertical shaft furnaces. As a result of the cross-flow of the oxygen-containing Schwel- and A gasification zone develops in the feed, that of the end of the feed runs diagonally through the material layer towards the discharge end.

The practical operation of these furnaces has shown that for the production of a gas of uniform quality, in particular uniform calorific value, and a good utilization of the smoldering and of the fuel to be gasified, the location of the gasification zone is of decisive importance. The gasification zone should develop in the fuel layer in such a way that at the discharge end of the furnace the combustible contained in the ash-rich fuel is as completely consumed as possible without any excess Smoldering and gasifying agent is used, which leads to fluctuations in the composition of the useful gas generated and to an undesirable drop in the already in many cases low calorific value of the gas. So far it has been extraordinary in practical operation difficult to adhere to these conditions with sufficient precision.

As a rule, it is a special property of ash-rich fuels that they both constant fluctuations in terms of their carbon content as well as their grain size are subject. These fluctuations cause constant changes in the position of the gasification zone. This is associated with the risk that either the combustible components of the fuel are incomplete are burned out or that breakthroughs of the gasification agent occur, which the mentioned Cause a decrease in the calorific value of the gas. You could see the fluctuations in carbon content and in the grain size of the fuel by a mixing plant or by sieving off an excess Remove the amount of the finest fuel. Meanwhile, the mixing plant would have such dimensions require that it would no longer be economically viable, and the sifting of some of the finest Method and device

for the generation of lean gas

uniform texture

by smoldering and gassing

ash-rich fuels

in a cross-flow furnace

Applicant:

Metallgesellschaft Aktiengesellschaft,
Frankfurt / M., Reuterweg 14

Dr.-Ing. Otto Hubmann, Bad Homburg v. d. Height,

and Dipl.-Ing. Paul Lange, Frankfurt / M.,

have been named as inventors

Fuel share would be associated with considerable fuel losses.

Attempts have already been made to reduce the speed of fuel passage through the furnace in this way set that despite the fluctuations in the carbon content and in the grain size of the fuel a sufficiently uniform gas quality is achieved. So you have with cross-flow furnaces, through which the fuel was moved through by means of a mechanical conveyor, the conveying speed of this Device regulated so that the fuel residue still had some residual carbon content. However, the fuel content of the discharged material represents a considerable loss. one tried to constantly control the position of the gasification zone in the furnace and then the Set good passage through the furnace. The control of the position of the gasification zone was hereby made by rods driven into the fuel layer from above. This remedy, however, was very cumbersome, required additional operating personnel and was still inadequate because with it no sufficiently accurate temperature measurements were possible. Attempts have also been made to determine the location of the Combustion zone through constant temperature measurements of the gases emerging from the fuel layer to monitor and determine. But even this remedy was practically unsuccessful because of the temperature fluctuations in the gases emerging from the fuel layer caused by the change in position

909 649/191

Claims (1)

3 4 the gasification zone, its lower part are relatively small in a known manner as dry, since only relatively small amounts of gas can be formed in and preheating zone. Of the Cross-flow through the fuel layer - gasification fuel is fed through a feed will. On the other hand, the fact that grate 3 is withdrawn from the bunker 1 and with the help the carbon content of the fuel changes, 5 of this grate in a layer of about 0.5 to 3 m, the outlet temperature of the gases influenced, so that advantageously at least 1.0 m thick through the Kamdie Temperature measurements and the movement through them vermer2. The migratory speeds Changes in the passage speed of the fuel are determined by the number of strokes The speed of the fuel through the furnace is not influenced by the grate, which can be adjusted continuously with the help of a sufficient to accommodate the fluctuations in the combination of adjustable grate drive 10 with speed bearing 11 to eliminate the generated gas. is provided. It has now been found that the oxygen content at the entry into the gasification chamber 2 is the of the gas flow, which at the outlet end of the furnace from fuel with the help of an ignition chamber 4 through the fuel layer emerges, ignited with the complete exhaustion of hot air or hot combustion gases. in the The carbon content of the fuel burns very quickly increases. Based on this knowledge, the fuel is gasified. To this end, will according to the invention the oxygen content of the partial gas - a mixture of air with water vapor and / or current, the gases returned from the material layer at the end of the furnace advantageously exit across the layer, constantly measured, and it is sucked through from top to bottom after the adhesive. Below The result of the measurement, the throughput speed of the grate, is a deviation from the outside air the material through the furnace either hand-sealed collecting chamber; 6 arranged from which the or advantageously set automatically. If the gases formed during the gasification increase with the help of an es Oxygen content based on an empirical value that is sucked out by fan 7 and a condensation in between If there is 2 and 5% oxygen in the gas, any direction is used for cooling and cleaning the throughput speed of the goods is increased. 25 are fed. Conversely, if the oxygen content drops too much, the gasification process is carried out in such a way that the the throughput speed of the material is dumped up to the end of the grate path completely expressive reduced. The practical operation has burned. This creates a dated shows that this type of control is reliable from the top to the bottom of the fuel layer is enough to keep the oxygen content of the gas constantly at an inclined reaction zone. The ausder Keep the same height and the position of the burnt residue is outside the furnace aeration zone Collected evenly in the fuel bed and, for example, in lorries 5 and safe from the power take-off to adjust. At the end of the gas collector ported. At the end of the gasification zone is below the chamber, a space is appropriately partitioned off Safety to ensure that only the partial gas flow, 35 grate in the gasification chamber a probe 8 which emerges from the layer of embers at the end of the stove, through which a constant partial flow of the at the is measured and that the gas is not generated by the measuring probe. is assumed from the entire space of the gas collecting chamber, which is working in a registering can be sucked. Oxygen meter 9 is examined for oxygen. The method is carried out in the 40. The measured values obtained in this way are used for regulation Way that at the end of the gasification section one of the feed uses in such a way that at one Probe is inserted into the gas space. With the help of increasing the oxygen content the speed of the this probe is constantly from the end zone of the grate drive and thus the migration speed. Gasification originating partial flow of the gases sucked off, increased speed of the fuel in the furnace and at one which then in an oxygen meter to its content 45 lowering of the oxygen content, the grate speed and is analyzed on oxygen. The value determined in this way reduces the fuel speed, provides a direct measure of the position of the transfer. This transfer can either be done by hand gassing zone. If the oxygen content is too low, or if necessary automatically. In this case the throughput speed of the goods is controlled by the measured values of the oxygen recorder reduces the furnace and if the oxygen 50 is too high a relay 12 drives the grate in such a way that the salary increased. With the help of this measure, it is the speed controller 11 attached to the transmission 10 possible, a gas of constant quality with increasing oxygen values an increase in to generate the highest yield of gas. The speed of the grate drive can be effected and a z. B. this display of the oxygen content by reducing the speed when the oxygen content electrical and mechanical transmission links with 55 falls. The throughput of the couple to the grate drive and in this way automatically increase or decrease the oven. To this Control of the material throughput automatically in such a way can the oxygen content and thus also the Depending on the oxygen content. Quality of those withdrawn from the fuel bed To carry out the method, the loading gases can automatically be adjusted to a specific, desired value Known facilities, such as traveling grids, are held at an incline of 60 degrees, which makes the operation of the Chambers with advancing grates or shaft furnace is extremely simplified,
ovens, serve. The following describes how the Method using an exemplary embodiment explains patent claims:
will. The cross-flow furnace is an inclined one Chamber with moving grate (lifting furnace) is based on 65 1. Process for generating lean gas lays. In the drawing, such a device is of uniform nature by smoldering and for example and shown schematically. The gas used for gasifying ash-rich fuels, such as washing the gasification of the ash-rich fuels hide and oil shale, in a cross-flow furnace The cross-flow furnace consists of an inclined under control of the passage speed Chamber 2, which is located under a bunker 1, 7 "of the fuel through the furnace, thereby marked